Since the 1980s, the development of electronic technology has brought about various changes in automobile manufacturing technology. Since the development of microcomputers has affected automobiles, the current air pollution level can be achieved, and thus combustion suitable for the discharge of exhaust gas satisfying desired criteria can be achieved, thereby making a great contribution to fuel economy.
It has been observed that there is no method of achieving a greater fuel saving effect and reducing exhaust gas using the current structures and materials of engines. The only method of reducing fuel consumption and suppressing exhaust gas further is for a driver to practice economical driving.
In general, the fuel consumption of a vehicle is lowest in an appropriate load range, and is high in low and high load ranges. Therefore, when appropriate load driving is performed, economical driving can be realized. However, conventional vehicles are not equipped with display devices indicating the amounts of fuel consumed or the extents of loads, so that drivers cannot be aware of load ranges in which their vehicles are being operated, with the result that they cannot drive the vehicles in appropriate load ranges.
From various experiments, it was proved that a difference equal to or greater than 20% occurred between the amount of fuel consumed at a speed of 100 km/H and the amount of fuel consumed at a speed of 130 km/H, and a difference equal to or greater than 30% occurred between the amount of fuel consumed for slow acceleration and the amount of fuel consumed for fast acceleration.
However, although drivers are aware that fuel consumption varies with the driving method, they cannot observe the variation, so that they cannot experience fuel consumption depending on the driving method, and thus do not practice economical driving.
In general, the amount of fuel consumed is measured in such a way that a measuring instrument for measuring the amount of fuel consumed is installed in a fuel supply line and the amount of fuel consumed is measured using it. However, the measuring instrument for measuring the amount of fuel consumed costs millions of won or tens of millions of won, which is a high price, and thus it is used for the purpose of developing engines in automobile manufacturers or automobile-related research laboratories, but it is impossible for drivers to know the amount of fuel consumed by their vehicles. Furthermore, in order to obtain the amount of fuel consumed and fuel efficiency, many drivers having interest in fuel efficiency estimate fuel efficiency using the amount of fuel consumed and the traveled distance based on the amount of fuel that is charged when a fuel tank is completely filled with fuel again after a trip odometer is set to 0 at the time of first completely filling the fuel tank with fuel and traveling over a certain distance is subsequently performed.
However, this method does not provide accurate measured values, cannot be utilized in real time, provides only average results, and is not utilized for the provision of real-time information.